DEPRECATED - Prefer the POST import endpoint which handles both create and update in one request.

Each CSV row must contain an Id column identifying the line item to update.

This endpoint behavior is duplicated by the POST import endpoint for rows that include Id.

CSV Requirements

Each row must contain an Id column with the line item identifier (GUID).

Maximum 5000 data rows allowed (excluding header).

Maximum file size: 100 MB.

First row must be a valid header with at minimum the Id column.

Mandatory field: Id (existing line item identifier).

Updatable fields: Any LineItem property (Quantity, SellingTerm, StartDate, EndDate, Comments, Description, CustomProperties.*, etc.).

Ignored fields: ExternalId, TxnUId, AdjustmentLineItems, IncentiveAdjustmentItems, PriceBreakupRecords, UsagePriceTiers, SfdcAttributes.

ProductCode column is stripped after parsing (not needed for updates).

Duplicate rows with the same Id are deduplicated (last wins).

Required Fields:

• cartId (route) - required
• file (form) - required; must be a .csv file with an Id column, max 100 MB